1. Technical Field
The present invention relates to a suction device, a suction system, and a suction method and, more particularly to a suction device, a suction system, and a suction method suitably used for sucking a viscous matter in clinical practice (for example, department of otorhinolaryngology).
2. Background Art
When a treatment is given to cure inflammatory disorders such as otitis media, rhinitis and sinusitis, and such a physical condition as cerumen impaction in a department of otorhinolaryngology, for example, it is necessary to suction and thereby remove otorrhea, rhinorrhea and cerumen. The suction and removal conventionally uses a flexible tube having a length of about 1.5 to 2 meters and a suction tube for nose or ear attached to a tip part of the tube via an adaptor which are connected to a suction device of an otorhinolaryngology unit. These suction tubes having very small outer and inner diameters owing to the anatomical basis that they are to be inserted into a very narrow passage, however, were often clogged when the tenacious otorrhea, rhinorrhea and cerumen were sucked. The suction tube thus obstructed during the suction resulted in an extra and time-consuming work, which was to interrupt the treatment to replace the suction tube or unclog the suction tube by sucking a fluid having a low viscosity (for example, water) thereinto before restarting the treatment.
Japanese Patent No. 2742765 discloses a device wherein a suction tube cavity and a side tube cavity divided from each other by a mid partition wall are provided in a suction tube as a suction catheter for sucking and thereby removing a tenacious matter or fluid such as phlegm in bronchia, and at least a notch is formed in the mid partition wall to constitute a shunt path between the tube cavities. The suction catheter is adapted to apply a negative pressure to the suction tube cavity while supplying air and fluid such as a physiological salt solution from the side tube cavity. Thus constituted, a tip part of the catheter can be prevented from getting stuck in a bronchial lumen, and the tenacious matter such as phlegm is wetted to be easily sucked, as described in paragraph [0009] of Japanese Patent No. 2742765.
However, the comparative experiments carried out by the present inventors, which will be described later, revealed that the suction catheter recited in Japanese Patent No. 2742765 demands an extensive duration of time that may impose an excessive strain on a patient before the suction is completed in the case where, for example, a fluid having a high viscosity, for example, 500 cps is to be sucked.